fix frictional inelastic no-slip case

ekiefl · Jan 3, 2025 · 522d4c6 · 522d4c6
1 parent 95571ff
commit 522d4c6
Showing 1 changed file with 4 additions and 5 deletions.
diff --git a/pooltool/physics/resolve/ball_ball/frictional_inelastic/__init__.py b/pooltool/physics/resolve/ball_ball/frictional_inelastic/__init__.py
@@ -65,12 +65,11 @@ def _resolve_ball_ball(rvw1, rvw2, R, u_b, e_b):
     # then slip condition is invalid so we need to calculate no-slip condition
     if not has_relative_velocity or np.dot(v12_c, v12_c_slip) <= 0:  # type: ignore
         # velocity tangent component for no-slip condition
-        D_v1_t = -(1.0 / 9.0) * (
-            2.0 * (rvw1[1] - rvw2[1])
-            + R * ptmath.cross(2.0 * rvw1[2] + 7.0 * rvw2[2], unit_x)
+        D_v1_t = -(1.0 / 7.0) * (
+            rvw1[1] - rvw2[1] + R * ptmath.cross(rvw1[2] + rvw2[2], unit_x)
         )
-        D_w1 = (5.0 / 9.0) * (
-            rvw2[2] - rvw1[2] + ptmath.cross(unit_x, rvw2[1] - rvw1[1]) / R
+        D_w1 = -(5.0 / 14.0) * (
+            ptmath.cross(unit_x, rvw1[1] - rvw2[1]) / R + rvw1[2] + rvw2[2]
         )
         rvw1_f[1] = rvw1[1] + D_v1_t
         rvw1_f[2] = rvw1[2] + D_w1